JP2005126439A - Cosmetic or dermatologic o/w emulsion having stable ph - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an O/W emulsion having a sufficient bacteriological securement and stable pH with time. <P>SOLUTION: The invention relates to the composition for topical use, in the form of an oil-in-water emulsion in which the mean size of the oil droplets ranges 50-1,000 nm, comprising 0.05-3 wt.%, based on total weight, of chlorohexidine salt, and at least one emulsifier having 9-18 of HLB, selected from a group comprising (i) a compound corresponding to formula R-(O-CH<SB>2</SB>-CH<SB>2</SB>)<SB>n</SB>-OH (I), [in the formula, R is an 8-30C (un)saturated linear or branched hydrocarbon residue, n is a number of 8-50, preferably 8-30], (ii) an addition product of 4-20 mol of ethylene oxide and one or more glycerol partial esters and (iii) mixtures thereof. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a cosmetic and / or dermatological composition in the form of an ultrafine oil-in-water emulsion which is obtained by phase inversion and can be brought to a stable pH by the introduction of a chlorhexidine salt. The invention also relates to the use of the composition in the form of the composition itself or a product impregnated with the composition, especially in the cosmetic field.

  In the cosmetic field, emulsions that give softness and do not give a greasy feel when applied to the skin, particularly oil-in-water (oil phase dispersed in an aqueous phase constituting a continuous phase) emulsion are generally used.

  Oil-in-water emulsions are generally stabilized by an oil-in-water emulsifying surfactant that is placed at the oil / water phase interface by an amphiphilic structure and thus stabilizes the dispersed oil droplets. Despite the presence of the emulsifier, the emulsion may have a tendency to phase separate (separation of the water and oil phases by oil release). Increasing the emulsifier content makes it possible to improve the stability of the emulsion. However, the presence of a high concentration of emulsifier causes uncomfortable problems with the composition obtained upon application, such as a rough or sticky or sticky feel, and a large amount of emulsifier results in harmlessness to the skin, eyes and scalp cause.

  In order to solve the stability problem of the conventional O / W emulsion, a specific “ultrafine” O / W emulsion in which the average diameter of the oil droplets constituting the oil phase is in a very specific range, ie 50 to 1000 nm. It has been proposed to prepare The O / W type ultrafine emulsion itself is generally obtained by a phase inversion emulsification technique.

  This technique is well known to those skilled in the art in its principles, in particular, an article published in Cosmetics & Toiletries, Vol. 106, December 1991, pp. 49-52, "Phase Inversion Emulsification", by Th. Forster et al .; And an article published in American Cosmetics and Perfumery, Vol. 87, December 1972, "Application of the phase-inversion-temperature method to the emulsification of cosmetics", T. Mitsui et al. The principle of this technique is as follows: The W / O emulsion (introduction of the aqueous phase into the oil phase) is used as the phase inversion temperature (PIT) of the system, ie Prepared at a temperature higher than the temperature at which the hydrophilic and lipophilic properties of the emulsifier reach equilibrium; at higher temperatures, ie above the phase inversion temperature (> PIT), the emulsion is water-in-oil and The emulsion is phase-inverted to an oil-in-water emulsion at the phase inversion temperature, which is achieved after first passing through the microemulsion state.

  These PIT emulsions are often very fluid. These appear bluish and can be translucent. However, these emulsions present stability problems, particularly pH stability problems that tend to change over time when the temperature exceeds the ambient temperature (ie, about 25 ° C.). In addition, their bacteriological protection also poses a problem because they are more difficult in conventional emulsions. However, it is important to obtain a composition with a stable pH and to obtain a composition that is well protected from a bacteriological standpoint.

Therefore, there is a need for a very fine O / W emulsion having a pH that is stable over time and exhibiting sufficient bacteriological protection.
Cosmetics & Toiletries, Vol. 106, December 1991, pp.49-52 American Cosmetics and Perfumery, Vol. 87, December 1972

  The Applicant has surprisingly found that the addition of chlorhexidine salt makes it possible to obtain O / W emulsions that have not only sufficient bacteriological protection but also a stable pH over time.

  The O / W emulsions of the present invention have the additional advantage of being commonly used because chlorhexidine salts are preservatives, and the addition of small amounts of these preservatives used in such compositions of the present invention is Enough to get good bacteriological protection. Furthermore, they have the general advantages of ultrafine emulsions, such as softness, freshness and comfort when applied.

  Literature “Physiochemical screening of antimicrobial agents as potential preservatives for submicron emulsions” obtained by Sznitowska, Malgorzata et al., European Journal of Pharmaceutical Sciences (2002), 15 (5), p.489-495, by high-pressure homogenization (HPH). Although described for the introduction of chlorhexidine salts as preservatives into the resulting fine O / W emulsions, the results described in this article show that the addition of such salts is a problem of healing and pH changes. Indicates that it should be avoided (page 493, right column).

  Emulsions according to the present invention contain certain emulsifying surfactants and have a certain amount of chlorhexidine salt, but unlike the prior art for fine emulsions obtained with HPH, allow sufficient stabilization of pH. .

The subject of the present invention is therefore a composition for topical application in the form of an oil-in-water emulsion comprising an oil phase dispersed in an aqueous phase, wherein the average diameter of the oil droplets is in the range from 50 nm (nanometers) to 1000 nm. At least one chlorhexidine salt in an amount ranging from 0.05 to 3% by weight relative to the total weight of the composition; and
The following formula (I):
R— (O—CH ₂ —CH ₂ ) _n —OH (I)
Wherein R represents a saturated or unsaturated, linear or branched hydrocarbon residue having 8 to 30 carbon atoms, and n is 8 to 50, preferably 8 to 30 Represents the number of ranges]
A compound corresponding to
An addition product of -4 to 20 mol of ethylene oxide and one or more glycerol partial esters;
A composition comprising at least one emulsifier having an HLB of 9 to 18 selected from the group consisting of -and mixtures thereof.

  This composition can in particular constitute a cosmetic or dermatological composition.

  The oil-in-water emulsion of the present invention is particularly obtained according to the phase inversion emulsification technique.

  As intended for topical application, the compositions of the present invention comprise a physiologically acceptable medium. The term “physiologically acceptable medium” is understood to mean a medium suitable for topical application to the skin or surface growth, ie suitable for the skin, mucous membranes, lips, hair and nails.

  The emulsion according to the invention may be somewhat fluid. These are generally fluids, which can have a viscosity in the range of, for example, 1 to 500 centipoise (1 to 500 mPa.s), preferably 1 to 200 centipoise (1 to 200 mPa.s). It is measured by Rheomat RM 180 (usually No. 1 or No. 2 rotor) at ambient temperature (25 ° C.). However, the emulsion according to the invention may also not be very fluid.

  As indicated above, a chlorhexidine salt used in the claimed amount, preferably in an amount of 0.1 to 2% of the total weight of the composition, results in a pH stable composition. Make it possible.

  Thus, the subject of the invention is also 0.05 to 3% by weight relative to the total weight of the composition for stabilizing the pH of oil-in-water emulsions whose mean oil droplet diameter is in the range of 50 nm to 1000 nm. Use of at least one chlorhexidine salt in an amount in the range of

  According to an essential feature of the composition according to the invention, the number average diameter of the liquid particles (or droplets) of the oil (or oil phase) in the dispersed aqueous phase is in the range from 50 nm to 1000 nm. Preferably, this average diameter ranges from 70 nm to 350 nm, more preferably from 70 nm to 300 nm.

  Furthermore, the composition according to the invention is characterized by a very low polydispersity, ie a very homogeneous droplet size. Generally, 90% of the ultrafine oil-in-water emulsions according to the invention have a number average diameter in the range of 70 to 350 nm. The difference between the maximum and minimum size of the droplets is generally 20 to 400 nm, preferably 30 to 200 nm, but in conventional emulsions (other than PIT emulsions or other than microemulsions) the maximum and minimum size of the droplets The difference in thickness is usually greater than 1000 nm.

  Chlorhexidine salts include in particular chlorhexidine digluconate, chlorhexidine diacetate and chlorhexidine hydrochloride. Preferably chlorhexidine digluconate is used.

  Of course, mixtures of these salts may be used.

  The amount of chlorhexidine salt in the composition of the present invention must be sufficient to provide the desired stability. This amount (weight of active substance) is in the range of 0.05 to 3% by weight, preferably 0.1 to 2% by weight, more preferably 0.15 to 1% by weight of the total weight of the composition.

  The nature of the oil phase of the emulsion according to the invention is not critical. The oily phase may thus consist of any compound known to be suitable for the production of oil-in-water emulsions, especially in the cosmetic or dermatological field. In particular, these compounds can be selected from plant, animal or mineral oils, natural or synthetic waxes and various other fatty substances, alone or as a mixture, these oils, in particular cosmetic oils, and other fats. The substance must be physiologically acceptable.

The oil phase generally comprises at least one oil. Among the oils that can be incorporated into the oil phase composition,
-Mineral oils such as liquid paraffin and liquid petrolatum;
-Animal hydrocarbon oils such as perhydrosqualene;
-Sweet almond oil, avocado oil, castor oil, cilantro oil, olive oil, jojoba oil, sesame oil, peanut oil, grape seed oil, rapeseed oil, coconut oil, hazelnut oil, karite butter, palm oil, apricot kernel oil, calophyllam oil, rice bran oil, Corn germ oil, wheat malt oil, soybean oil, sunflower oil, evening primrose oil, safflower oil, passiflora oil, rye oil, or sold by Sterineries Dubois or sold under the trade names Mylyol 810, 812 and 818 Plant-derived hydrocarbon oils such as caprylic / capric triglycerides such as
-Perserine oil, fatty acid esters, such as butyl myristate, isopropyl myristate, cetyl myristate, isopropyl palmitate, 2-ethylhexyl palmitate, isopropyl adipate, ethylhexyl adipate, butyl stearate, hexadecyl stearate, isopropyl stearate Esters extracted from lanolinic acid such as alert, octyl stearate, isocetyl stearate, decyl oleate, hexyl laurate, propylene glycol dicaprylate, isopropyl lanolate or isocetyl lanolate, dioctyl cyclohexane, isoparaffin and Synthetic oils such as fatty acid esters such as poly-α-olefins;
- dicaprylyl ether (CTFA name: dicaprylyl ether _{(Dicaprylyl ether)); C 12} -C 15 ethers such as benzoate fatty alcohols (Finetex Inc. Finsolv TN);
-Volatile or non-volatile paraffin oils and their derivatives, petrolatum, polydecene, isohexadecane, isododecane, substantially linear or fractions derived from minerals or syntheses such as hydrogenated polyisobutenes such as Parleam® oil. Branched hydrocarbons;
-Mixtures thereof such as lauryl alcohol, cetyl alcohol, myristyl alcohol, stearyl alcohol, palmityl alcohol, oleyl alcohol, linoleyl alcohol, 2-octyldodecanol, and cetearyl alcohol (mixture of cetyl alcohol and stearyl alcohol), etc. Of fatty alcohols containing from 8 to 26 carbon atoms;
-Acetylglycerides;
-Octanoates and decanoates of alcohols and polyhydric alcohols such as glycol and glycerol; lisinoleates of alcohols and polyhydric alcohols such as cetyl;
-Fluorinated and perfluorinated oils-lanolin; hydrogenated lanolin; acetylated lanolin;
-Volatile or non-volatile polymethylsiloxanes (PDMS) with linear or cyclic silicone chains that are liquid or pasty at ambient temperature, especially cyclopolydimethylsiloxanes (cyclomethicone) such as cyclohexasiloxane A polydimethylsiloxane having 2 to 24 carbon atoms in the pendant position alkyl group, alkoxy group or phenyl group, or alkyl group, alkoxy group or phenyl group at the silicone chain end position; or phenyl trimethicone, phenyl dimethicone; Phenylated silanes such as corn, phenyltrimethylsiloxydiphenylsiloxane, diphenyldimethicone, diphenylmethyldiphenyltrisiloxane, (2-phenylethyl) trimethylsiloxysilicate or polymethylphenylsiloxane. Volatile or non-volatile silicone oils, such as corn and the like.

  The term “hydrocarbon oil” in the oil list mentioned above is any oil mainly containing carbon and hydrogen atoms and optionally containing ester, ether, fluorinated carboxylic acid and / or alcohol groups. Is understood to mean.

  One oil or a mixture of several oils as indicated above can be used.

  According to a particular embodiment of the invention, the composition comprises at least one oil selected from mineral oils, fatty acid esters, and mixtures thereof.

  According to another specific embodiment of the invention, the composition comprises at least one emollient selected from the oils indicated above, in particular 2-ethylhexyl palmitate, dicaprylyl ether, and mixtures thereof. Contains agents.

  Conventionally, the aqueous phase can contain, in addition to water, one or more water-soluble solvents selected from polyols (or polyhydric alcohols), water-soluble lower alcohols, and mixtures thereof. The term “lower alcohol” is understood to mean an alcohol containing from 1 to 8 carbon atoms. Polyols include, for example, glycerol; glycols such as propylene glycol or butylene glycol; sorbitol; sugars such as glucose, fructose, maltose, lactose, sucrose; and mixtures thereof. Examples of the lower alcohol include ethanol, isopropanol, butanol and a mixture thereof.

The oil-in-water emulsion according to the present invention is preferably
(I) 50 to 98%, more preferably 70 to 96% by weight of aqueous phase of the total weight of the composition;
(Ii) 2 to 50%, more preferably 4 to 30% by weight of the oil phase of the total weight of the composition.

  The emulsion according to the invention generally comprises one or more emulsifying surfactants. In addition, they can contain certain co-emulsifiers, whose role is to substantially reduce the amount of emulsifying surfactant required for the preparation of the emulsion during the preparation of the emulsion.

The composition of the present invention comprises:
The following formula (I):
R— (O—CH ₂ —CH ₂ ) _n —OH (I)
Wherein R represents a saturated or unsaturated, linear or branched hydrocarbon residue having 8 to 30 carbon atoms, and n is 8 to 50, preferably 8 to 30 Represents the number of ranges]
A compound corresponding to
An addition product of -4 to 20 mol of ethylene oxide and one or more glycerol partial esters;
-And at least one emulsifier having a HLB (Hydrophilic Lipophilic Balance) of 9 to 18 selected from the group consisting of these.

  For example, as compounds of formula (I), addition products of ethylene oxide and behenyl alcohol, such as Beheneth-9 (9 mol ethylene oxide) and Beheneth-10 (10 mol ethylene oxide); cetyl alcohol or stearyl alcohol or mixtures thereof and ethylene oxide Addition products, in particular they contain 12 to 20 mol of ethylene oxide, such as Ceteareth-12, Ceteareth-13, Ceteareth-14, Ceteareth-15, Ceteareth-16, Ceteareth-17, Ceteareth-18 or Ceteareth-20 Addition product obtained from a mixture of cetyl alcohol and stearyl alcohol (cetearyl alcohol); addition product obtained from cetyl alcohol such as Ceteth-14, Ceteth-15, Ceteth-16 or Ceteth-20; , Steareth-14, Steareth-15, Steareth-16 or Steareth-20 Addition products obtained from Le, and mixtures of these various emulsifying agents can be used.

As emulsifiers, addition products of 4 to 20 mol of ethylene oxide and one or more glycerol partial esters can also be used. The term “glycerol partial ester” means a mixture of monoglycerides, diglycerides and triglycerides of C ₁₀ -C ₂₀ fatty acids obtained, for example, by esterifying 1 mol of glycerol with 1 or 2 mol of C ₁₀ -C ₂₀ fatty acids. It is understood as follows.

Furthermore, the emulsion according to the invention can further comprise one or more coemulsifiers. This or these coemulsifiers are selected, for example, from C ₁₆ -C ₂₂ fatty alcohols, or esters of C ₃ -C ₆ polyols and C ₁₄ -C ₂₂ fatty acids, and mixtures thereof. Examples of co-emulsifiers include cetyl alcohol, stearyl alcohol, cetearyl alcohol (a mixture of cetyl alcohol and stearyl alcohol), glyceryl stearate, and mixtures thereof.

  As a mixture comprising an emulsifier and a co-emulsifier, for example, a mixture sold under the trade name Emulgade SEV of Cognis, including Ceteareth-20, Ceteareth-12, hydrogenated coconut oil and cetearyl alcohol can be used.

  The amount of emulsifier and coemulsifier in the composition of the present invention is generally in the range of 0.05 to 30% by weight, preferably 0.5 to 20% by weight, more preferably 1 to 10% by weight of the total weight of the composition. is there.

  The composition according to the invention can also contain any adjuvants or additives commonly used in the art, in particular in the field of cosmetics or dermatology.

  Among the usual adjuvants that can be present in the aqueous and / or oily phase of the emulsion according to the invention (depending on the water-soluble or fat-soluble nature of these adjuvants), ionic or non-ionic gelling agents and thickenings Agents; hydrophilic or lipophilic cosmetic or dermatological active ingredients; fragrances; preservatives; metal ion blockers (EDTA); pigments; nacres; inorganics such as talc, kaolin, silica powder or polyethylene powder Or organic fillers; soluble dyes; sunscreen agents; basic or acidifying agents; compounds that improve the softness and slipperiness of the composition upon application, for example cetyl dimethicone, and mixtures thereof . The amounts of these various adjuvants are those commonly used in the art, for example from 0.01 to 20% of the total weight of the composition.

  The choice of cosmetic or dermatological active ingredients that can be used in the composition of the invention depends on the purpose of the composition. Examples of active ingredients that can be used in the present invention include bactericides such as octopirox, triclosan and triclocarban; hydroxy acids (α-hydroxy acids and β-hydroxy acids) such as lactic acid, glycolic acid, citric acid, salicylic acid and the like. Epidermis stripping and anti-aging agents such as derivatives; essential oils; vitamins, especially retinol (vitamin A), ascorbic acid (vitamin C), tocopherol (vitamin E), nicotinamide (vitamin PP or B3), panthenol (vitamin B5) and Derivatives thereof (eg esters); coenzymes, in particular coenzyme Q10 or ubiquinones; enzymes such as lipases, proteases, phospholipases, cellulases, peroxidases, in particular lactoperoxidase, catalase or superoxy Dodismutase, and plant extracts containing the aforementioned enzymes; yeasts such as Saccharomyces cerevisiae; steroids; antioxidants and free radical scavengers; polyols (glycerol, sorbitol, sugars), protein hydrolysates, urea and these Moisturizers such as mixtures containing; slimming agents such as caffeine; anti-elastase and anti-collagenase agents; oily skin treatments; and mixtures thereof.

  As derivatives of salicylic acid, 5- (n-octanoyl) salicylic acid (CTFA name: Capryloyl Salicylic Acid), 5- (n-decanoyl) salicylic acid, 5- (n-dodecanoyl) salicylic acid, 5- (n- Octyl) salicylic acid, 5- (n-heptyloxy) salicylic acid, 5- (tert-octyl) salicylic acid, 5-butoxysalicylic acid, 5-ethoxysalicylic acid, 5-methoxysalicylic acid, 5-propoxysalicylic acid, 5-methylsalicylic acid, 5- Particular mention is made of ethylsalicylic acid, 5-propylsalicylic acid, and mixtures thereof. These acids can be optionally salified with a base.

  Examples of steroids include, for example, dehydroepiandrosterone (or DHEA), and (1) biological derivatives and precursors thereof, especially DHEA salts and esters such as DHEA sulfate and salicylate, 7-hydroxy-DHEA, 7-keto-DHEA, or esters of 7-hydroxy and 7-keto-DHEA, especially 3-β-acetoxy-7-oxo-DHEA, and (2) chemical derivatives and precursors thereof, particularly diosgenin or helogenin Mention may also be made of sapogenins and / or their derivatives such as hecogenin acetate and / or natural extracts containing them, in particular extracts of the genus Yam, such as natural yam.

  The sunscreen agent (or UV screening agent) optionally present in the composition can be selected from organic screening agents, physical screening agents and mixtures thereof.

  The compositions of the present invention can include any UV-A and UV-B screening agents that can be used in the cosmetic field as chemical screening agents that can be used in the compositions of the present invention.

Examples of UV-B screening agents include (1) salicylic acid derivatives, particularly homomenthyl salicylate and octyl salicylate;
(2) Cinnamic acid derivatives, in particular 2-ethylhexyl p-methoxycinnamate sold under the trade name Parsol MCX from Givaudan;
(3) Liquid β, β′-diphenyl acrylate derivatives, in particular 2-ethylhexyl α-cyano-β, β′-diphenyl acrylate or octocrylene sold under the name Uvinul N539 by the company BASF;
(4) p-aminobenzoic acid derivative;
(5) 4-Methylbenzylidene camphor sold by Merck under the name Eusolex 6300;
(6) 2-Phenylbenzimidazole-5-sulfonic acid sold by Merck under the trade name Eusolex 232;
(7) 1,3,5-triazine derivatives, in particular:
-2,4,6-tris [p- (2'-ethylhexyl-1'-oxycarbonyl) anilino] -1,3,5-triazine sold by BASF under the name Uvinul T150, and -Sigma Dioctylbutamide triazone sold under the name Uvasorb HEB by 3V;
(8) A mixture of these screening agents can be mentioned.

Examples of UV-A screening agents include (1) dibenzoylmethane derivatives, especially 4- (tert-butyl) -4′-methoxydibenzoylmethane sold under the trade name Parsol 1789 by the company Givaudan;
(2) Benzene-1,4- [di (3-methylidenecamphor-10-sulfone)], optionally in a partially or fully neutralized form, sold by Chimex under the trade name Mexoryl acid;
(3) Benzophenone derivatives, for example:
-2,4 dihydroxybenzophenone (benzophenone-1);
-2,2 ', 4,4'-tetrahydroxybenzophenone (benzophenone-2);
-2-hydroxy-4-methoxybenzophenone (benzophenone-3) sold under the name Uvinul M40 by the company BASF;
-2-hydroxy-4-methoxybenzophenone-5-sulfonic acid (benzophenone-4) and its sulfonate form (benzophenone-5) sold by BASF under the name Uvinul MS40;
-2,2'-dihydroxy-4,4'-dimethoxybenzophenone (benzophenone-6);
-5-chloro-2-hydroxybenzophenone (benzophenone-7);
-2,2'-dihydroxy-4-methoxybenzophenone (benzophenone-8);
-Disodium salt of 2,2'-dihydroxy-4,4'-dimethoxybenzophenone-5,5'-disulfondioic acid (benzophenone-9);
-2-hydroxy-4-methoxy-4'-methylbenzophenone (benzophenone-10);
-Benzophenone-11;
-2-hydroxy-4- (octyloxy) benzophenone (benzophenone-12);
(4) a polyorganosiloxane containing a silane derivative or a benzophenone group;
(5) Anthranilate, especially menthyl anthranilate sold under the trade name Neo Heliopan MA by Haarmann &Reimer;
(6) Compounds containing at least two benzazolyl groups or at least one benzodiazolyl group per molecule, in particular 1,4-bis (benzimidazolyl) phenylene-3,3 ′, 5,5 sold by the company Haarmann & Reimer '-Tetrasulfonic acid and its salts;
(7) N-substituted benzimidazolyl benzazoles or silicone derivatives of benzofuranyl-benzazole as disclosed in patent application EP-A-1 028 120, in particular:
-2- [1- [3- [1,3,3,3-tetramethyl-1-[(trimethylsilyl) oxy] disiloxanyl] propyl] -1H-benzimidazol-2-yl] benzoxazole;
-2- [1- [3- [1,3,3,3-tetramethyl-1-[(trimethylsilyl) oxy] disiloxanyl] propyl] -1H-benzimidazol-2-yl] benzothiazole;
-2- [1- (3- (trimethylsilanyl) propyl) -1H-benzimidazol-2-yl] benzoxazole;
-6-methoxy-1,1'-bis (3- (trimethylsilanyl) propyl) -1H, 1'H- [2,2 '] bibenzimidazolylbenzoxazole;
-2- [1- (3- (trimethylsilanyl) propyl) -1H-benzimidazol-2-yl] benzothiazole;
(8) Triazine derivatives, especially 2,4-bis [4- (2-ethylhexyloxy) -2-hydroxyphenyl] -6- (4-methoxyphenyl) sold under the trade name Tinosorb S from Ciba Geigy 1,3,5-triazine and 2,2′-methylenebis [6- (2H-benzotriazol-2-yl) -4- (1,1) sold under the name Tinosorb M by Ciba Geigy , 3,3-tetramethylbutyl) phenol];
(9) These mixtures are mentioned.

  Mixtures of several of these screening agents, and mixtures of UV-B and UV-A screening agents, and mixtures with physical screening agents can also be used.

  Physical shielding agents include titanium oxide (amorphous titanium dioxide or crystalline titanium dioxide in the form of rutile and / or anatase), zinc oxide, iron oxide, zirconium oxide, cerium oxide or mixtures thereof. These metal oxides can be in the form of molecules (nanopigments) having a micrometer or nanometer size. The average diameter of the molecules in the form of nanopigments is, for example, in the range from 5 to 100 nm. Nanopigments are preferably used in the compositions of the present invention.

  Of course, those skilled in the art will recognize that the advantageous attributes inherently provided in the compositions according to the present invention are not adversely affected or substantially unaffected by the intended addition. Care will be taken to select possible compounds to be added to such compositions.

The emulsion according to the present invention is usually obtained by phase inversion treatment. This preparation procedure is characterized by the following:
(1) (A) an oil phase (B) at least one emulsifier and optionally a co-emulsifier (D) comprising at least one oil and optionally other oils and fatty substances and a fat-soluble adjuvant, stable at the phase inversion temperature ) Mixing the aqueous phase to prepare a normal emulsion, containing water and optionally a water-soluble solvent and a water-soluble adjuvant, stable at the phase inversion temperature,
(2) heating the emulsion to a temperature within or above the phase inversion range, or preparing the emulsion directly at such temperature,
after that,
(3) Cool the emulsion and add chlorhexidine salt and optionally an adjuvant or active ingredient unstable at the phase inversion temperature, such as a fragrance.

  Utilizing other methods, for example, adding only a portion of the aqueous phase (eg 10-30% of the aqueous phase) during the preparation of the emulsion and then diluting the emulsion with the remaining aqueous phase containing the chlorhexidine salt after cooling It is also possible to do.

  The phase inversion temperature range can be observed visually by observing changes in the transparency and opacity of the emulsion, which is initially opaque in the form of a W / O emulsion and then microscopic. It becomes transparent when it becomes an emulsion, becomes opaque when it is again in the form of an O / W emulsion, and becomes transparent when cooled again below the phase inversion temperature. This temperature range is also determined for a given composition by measuring the conductivity of a sample of the composition to be heated. When the phase inversion range is reached, the conductivity of the emulsion increases rapidly: in the phase inversion range, an increase in conductivity of about 50 microsiemens per centimeter can be observed over a temperature range of 5 to 15 ° C. There can be only about 5 microsiemens per centimeter during the equivalent temperature range outside the phase inversion range.

  The composition according to the invention can be provided in particular in the form of a somewhat fluid lotion or emulsion. They can be used as such or as an aerosol or in the form of a spray.

  The composition according to the invention is particularly suitable for the care, protection and / or hygiene products of the face and / or body skin, scalp or mucous membrane, for example face, hand or body protection, treatment or care spray, or skin, An emulsion or lotion for the body may be constructed for the protection or care of the scalp or mucous membranes or for removing and / or washing makeup from the skin and / or lips. They can be used, for example, to moisturize and / or tighten the skin and / or nourish the skin.

  The compositions according to the invention also include anti-sun products for protecting the body and / or facial skin from the harmful effects of the sun or UV rays, as well as products for making up keratin materials, in particular the skin and / or lips. Can be configured.

  The subject of the present invention is the cosmetic use of the composition for the treatment, protection, care, makeup removal and / or cleaning of the skin and / or lips and / or skin and / or lips makeup.

  The subject of the present invention is also a method for cosmetic treatment of the skin and / or lips, characterized in that the composition is applied to the skin and / or lips. The type of treatment can vary depending on the function of the active ingredient present in the composition.

  According to another embodiment of the invention, the composition according to the invention can be used for impregnation of water-insoluble substrates to form products that are applied to the skin, such as wipes. The water-insoluble substrate can be selected from the group consisting of woven materials such as sheets, balls or films, non-woven materials, foams, sponges and stuffed cotton. It is particularly natural (linen, wool, cotton, silk) or synthetically derived (cellulose derivatives, viscose, polyvinyl derivatives, polyesters such as poly (ethylene) terephthalate, polyolefins such as polyethylene or polypropylene, polyamides such as nylon, etc. Or an acrylic derivative) fiber. Nonwovens are generally described in Riedel's "Nonwoven Bonding Methods & Materials", Nonwoven World (1987). These substrates are obtained according to the usual methods in the preparation of nonwoven fabrics. According to a particular embodiment of the invention, the insoluble substrate is attached to the support by known methods for grafting biocides to fibers, in particular according to the invention. Preservatives can be included.

  The substrate can include one or more layers having the same or different properties, and can have elasticity and flexibility properties, and other properties suitable for the desired use. Said substrate may comprise two parts having different properties of elasticity, for example as disclosed in specification WO-A-99 / 13861, or disclosed in specification WO-A-99 / 25318 Can include a single layer with different densities as described, or can include two layers of different fabrics as disclosed in the specification WO-A-98 / 18441.

  The substrate can have any size and any shape suitable for the desired application. It usually has a surface area of 0.005 square meters to 0.1 square meters, preferably 0.01 square meters to 0.05 square meters. It is preferably provided in the form of a rectangular wipe or a round compress.

  The final product comprising the substrate and impregnating composition is usually in a wet state, and the degree of impregnation of the composition is, for example, 200 to 1000% by weight of the composition relative to the substrate, preferably 250 to 350% by weight. % Range. Techniques for impregnating substrates with compositions are well known in the art and are all applicable to the present invention. In general, the impregnating composition is applied to the substrate by one or more techniques including dipping, painting, vaporizing, and the like.

  Dry form in powder, fine or film form by removing water from the composition after impregnating the substrate or by any known means of practice such as multi-layer welding and bonding by thermal or ultrasonic route It is also possible to form a product (or wipe) in a dry state by impregnating the substrate with the composition. In the latter embodiment, the composition is dried by any known means: atomization, lyophilization or other similar methods.

  Thus, a wet or dry wipe can be obtained according to the intended use. Wet wipes can be used as such, but dry wipes are moistened before use.

  Accordingly, another subject of the present invention is (A) a water-insoluble substrate, (B) a product comprising said composition added or impregnated on said substrate, the use of said product in the cosmetic or dermatological field, In particular skin care (nourishing, tightening, moisturizing), makeup removal and / or washing.

  This product may in particular constitute a wipe for caring for and / or treating the skin and / or a wipe for removing and / or cleaning makeup from the skin and / or eyes.

  The subject of the present invention is also the cosmetic use of said products for skin and / or eye care, makeup removal and / or cleaning.

  The examples shown below are intended to provide a better understanding of the present invention and are not intended to limit its essence. The indicated amounts are weight percent unless otherwise stated. The names are chemical names and CTFT names, depending on the compound.

Example 1 according to the invention: Fluid milky phase A
Mineral oil 5%
Dicaprylyl ether (Cognis Cetiol OE) 3%
Mixture of Ceteareth-20, Ceteareth-12, hydrogenated palm oil and cetearyl alcohol
(Cognis' Emulgade SEV) 3%
Ceteareth-20 (Cognis Emulgin B2) 1%
2-ethylhexyl palmitate 3%
Cetyl Dimethicone (Abil Wax 9801 from Goldschmidt) 0.1%

Phase B
Glycerol 5%
15% distilled water

Phase C
Palm oil 0.2%
Fragrance 0.4%

Phase D
Chlorhexidine digluconate 0.25%
Amount to make the whole distilled water 100%

procedure:
Phases A and B were heated separately with stirring and homogenized. Phase B was poured into Phase A with slow stirring and the mixture was heated to a phase inversion temperature (PIT) that was a temperature of about 60 to 80 ° C. The resulting water-in-oil emulsion became almost transparent during heating. When the emulsion turned white, heating was discontinued and phase C was poured into the emulsion with slow stirring and then diluted by adding phase D as soon as the emulsion became clear during cooling.

  A slightly bluish, fluid (about 1 centipoise viscosity) oil-in-water emulsion was obtained. Even after storage at various temperatures, the pH remained stable as shown in the following table:

Furthermore, the microbiological protection is good.
This emulsion can be used as it is or as a spray, or it can be impregnated into a nonwoven support to make up a wipe applied to the face or body, and nourish and moisturize, for example, the skin Can be used for feeding and tightening.

Comparative Example 2:
Phase A
Mineral oil 5%
Dicaprylyl ether (Cognis Cetiol OE) 3%
Mixture of Ceteareth-20, Ceteareth-12, hydrogenated palm oil and cetearyl alcohol
(Cognis' Emulgade SEV) 3%
Ceteareth-20 (Cognis Emulgin B2) 1%
2-ethylhexyl palmitate 3%
Cetyl Dimethicone (Abil Wax 9801 from Goldschmidt) 0.1%

Phase B
Glycerol 5%
15% distilled water
Methylparaben 0.2%

Phase C
Palm oil 0.2%
Fragrance 0.4%

Phase D
Imidazolidinyl urea (Germall 115) 0.3%
Amount to make the whole distilled water 100%

This procedure is the same as the procedure of the first embodiment according to the present invention.
In this example, chlorhexidine digluconate was replaced with another preservative (Germall 115).
The pH was observed to change over time as shown in the following table:

  Furthermore, microbiological protection was found to be insufficient.

Comparative Example 3:
Phase A
Mineral oil 5%
Dicaprylyl ether (Cognis Cetiol OE) 3%
Mixture of Ceteareth-20, Ceteareth-12, hydrogenated palm oil and cetearyl alcohol
(Cognis' Emulgade SEV) 3%
Ceteareth-20 (Cognis Emulgin B2) 1%
2-ethylhexyl palmitate 3%
Cetyl Dimethicone (Abil Wax 9801 from Goldschmidt) 0.1%

Phase B
Glycerol 5%
15% distilled water
Methylparaben 0.2%

Phase C
Palm oil 0.2%
Fragrance 0.4%

Phase D
Chlorphenezine 0.25%
Amount to make the whole distilled water 100%

This procedure is the same as the procedure of the first embodiment according to the present invention.
In this example, chlorhexidine digluconate of Example 1 was replaced with another preservative (chlorphenidine).
The pH was observed to change over time as shown in the following table:

  Furthermore, the microbiological protection is insufficient.

Example 4 according to the invention: flowable emulsion phase A
Cyclomethicone 4.5%
Dicaprylyl ether (Cognis Cetiol OE) 3%
Mixture of Ceteareth-20, Ceteareth-12, hydrogenated palm oil and cetearyl alcohol
(Cognis' Emulgade SEV) 3%
Ceteareth-15 (Mogital CS15 from Cognis) 1.5%
Glyceryl stearate 0.9%
Fragrance 0.7%

Phase B
Glycerol 5%
15% distilled water
Methylparaben 0.2%

Phase C
Ethyl alcohol 3%

Phase D
Chlorhexidine digluconate 0.25%
Amount to make the whole distilled water 100%

This procedure is the same as that in the first embodiment.
A slightly bluish, fluid (about 1 centipoise viscosity) oil-in-water emulsion was obtained. Even after storage at various temperatures, the pH remained stable as shown in the following table:

  Furthermore, the microbiological protection is good.

  This emulsion can be used as it is or as a spray, or it can be impregnated into a nonwoven support to make up a wipe applied to the face or body, and nourish and moisturize, for example, the skin Can be used for feeding and tightening.

Claims (14)

A composition for topical application in the form of an oil-in-water emulsion comprising an oil phase dispersed in an aqueous phase, wherein the average diameter of the oil droplets is in the range of 50 nm to 1000 nm, and 0.05% relative to the total weight of the composition At least one chlorhexidine salt in an amount ranging from 3% to 3% by weight, and
The following formula (I):
R— (O—CH ₂ —CH ₂ ) _n —OH (I)
Wherein R represents a saturated or unsaturated, linear or branched hydrocarbon residue having 8 to 30 carbon atoms, and n is 8 to 50, preferably 8 to 30 Represents the number of ranges]
A compound corresponding to
An addition product of -4 to 20 mol of ethylene oxide and one or more glycerol partial esters;
A composition comprising at least one emulsifier having an HLB of 9 to 18 selected from the group consisting of -and mixtures thereof.   2. Composition according to claim 1, characterized in that it is obtained according to a phase inversion emulsification technique.   Composition according to claim 1 or 2, characterized in that the chlorhexidine salt is selected from chlorhexidine digluconate, chlorhexidine diacetate, chlorhexidine hydrochloride, and mixtures thereof.   4. Composition according to any one of the preceding claims, characterized in that the amount of chlorhexidine salt ranges from 0.1 to 2% by weight of the total weight of the composition.   The composition according to any one of claims 1 to 4, characterized in that the oil phase comprises at least one oil selected from mineral oils, fatty acid esters, and mixtures thereof.   6. Composition according to any one of the preceding claims, characterized in that the aqueous phase comprises 50 to 98% by weight of the total weight of the composition.   7. Composition according to any one of the preceding claims, characterized in that the emulsifier is selected from the product of addition of ethylene oxide with behenyl alcohol, cetyl alcohol, stearyl alcohol and mixtures thereof. . C ₁₆ -C ₂₂ fatty alcohols or partial esters of _C 3 -C ₆ polyols with _C 14 _{-C 22} fatty acids, and characterized in that it further comprises a co-emulsifier mixtures thereof, claims 1 8. The composition according to any one of 7 above.   9. Composition according to claim 8, characterized in that the amount of emulsifier and coemulsifier ranges from 0.05 to 30% by weight of the total weight of the composition.   10. Composition according to any one of the preceding claims, characterized in that it constitutes a cosmetic or dermatological composition.   11. Composition according to any one of the preceding claims, characterized in that it constitutes a product for the care, protection and / or hygiene of facial and / or body skin, scalp or mucous membranes.   A product comprising: (A) a water-insoluble substrate; and (B) a composition according to any one of claims 1 to 9 added or impregnated on said substrate.   17. A product according to claim 15 or 16, characterized in that it constitutes a wipe for caring for and / or treating the skin, or a wipe for removing and / or cleaning makeup from the skin and / or eyes.   At least one chlorhexidine in an amount ranging from 0.05 to 3% by weight relative to the total weight of the composition for stabilizing the pH of an oil-in-water emulsion wherein the average diameter of the oil droplets is in the range from 50 nm to 1000 nm Use of salt.